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Sep 22, 2013
09/13

by
L. L. Salcedo

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A definition is given, in the framework of stochastic quantization, for the dynamics of a system composed of classical and quantum degrees of freedom mutually interacting. It is found that the theory breaks reflection positivity, and hence it is unphysical. The Feynman rules for the Euclidean vacuum expectation values are derived and the perturbative renormalizability of the theory is analyzed. Contrary to the naive expectation, the semiquantized theory turns out to be less renormalizable, in...

Source: http://arxiv.org/abs/hep-th/9410007v4

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Jul 20, 2013
07/13

by
L. L. Salcedo

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The anomaly implies an obstruction to a fully chiral covariant calculation of the effective action in the abnormal parity sector of chiral theories. The standard approach then is to reconstruct the anomalous effective action from its covariant current. In this work we use a recently introduced formulation which allows to directly construct the non trivial chiral invariant part of the effective action within a fully covariant formalism. To this end we develop an appropriate version of Chan's...

Source: http://arxiv.org/abs/0804.2118v2

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Sep 18, 2013
09/13

by
L. L. Salcedo

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After formulating a no-go theorem for perfect quantum-classical hybrid systems, a new consistency requirement based on standard statistical considerations is noted. It is shown that such requirement is not fulfilled by the mean-field approach, nor by the statistical ensemble approach. Further unusual features of the latter scheme are pointed out.

Source: http://arxiv.org/abs/1201.4237v1

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Sep 17, 2013
09/13

by
L. L. Salcedo

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The coupling of spin 0 and spin 1 external fields to Dirac fermions defines a theory which displays gauge chiral symmetry. Quantum mechanically, functional integration of the fermions yields the determinant of the Dirac operator, known as the chiral determinant. Its modulus is chiral invariant but not so its phase, which carries the chiral anomaly through the Wess-Zumino-Witten term. Here we find the remarkable result that, upon removal from the chiral determinant of this known anomalous part,...

Source: http://arxiv.org/abs/0807.1696v1

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Sep 22, 2013
09/13

by
L. L. Salcedo

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Using the technique of labeled operators, compact explicit expressions are given for all traced heat kernel coefficients containing zero, two, four and six covariant derivatives, and for diagonal coefficients with zero, two and four derivatives. The results apply to boundaryless flat space-times and arbitrary non Abelian scalar and gauge background fields.

Source: http://arxiv.org/abs/hep-th/0409140v2

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Sep 19, 2013
09/13

by
L. L. Salcedo

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It shown that the quantum-classical dynamical bracket recently proposed in J. Chem. Phys. 124, 201104 (2006) fails to satisfy the Jacobi identity.

Source: http://arxiv.org/abs/quant-ph/0701054v1

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Sep 18, 2013
09/13

by
L. L. Salcedo

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Explicit exact formulas are presented, up to fourth order in a strict chiral covariant derivative expansion, for the normal parity component of the Euclidean effective action of even-dimensional Dirac fermions. The bosonic background fields considered are scalar, pseudo-scalar, vector and axial vector. No assumptions are made on the internal symmetry group and, in particular, the scalar and pseudo-scalar fields need not be on the chiral circle.

Source: http://arxiv.org/abs/hep-th/0012166v2

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Sep 18, 2013
09/13

by
L. L. Salcedo

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The fermions of the Standard Model are integrated out to obtain the effective Lagrangian in the sector violating P and CP at zero temperature. We confirm that no contributions arise for operators of dimension six or less and show that the leading operators are of dimension eight. To assert this we explicitly compute one such non-vanishing contribution, namely, that with three Z^0, two W^+ and two W^-. Terms involving just gluons and W's are also considered, however, they turn out to vanish in...

Source: http://arxiv.org/abs/1102.2400v1

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Sep 22, 2013
09/13

by
L. L. Salcedo

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The temperature dependence of the anomalous sector of the effective action of fermions coupled to external gauge and pseudo-scalar fields is computed at leading order in an expansion in the number of Lorentz indices in two and four dimensions. The calculation preserves chiral symmetry and confirms that a temperature dependence is compatible with axial anomaly saturation. The result checks soft-pions theorems at zero temperature as well as recent results in the literature for the pionic decay...

Source: http://arxiv.org/abs/hep-th/9807221v2

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Sep 20, 2013
09/13

by
L. L. Salcedo

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An expansion in the number of spatial covariant derivatives is carried out to compute the $\zeta$-function regularized effective action of 2+1-dimensional fermions at finite temperature in an arbitrary non-Abelian background. The real and imaginary parts of the Euclidean effective action are computed up to terms which are ultraviolet finite. The expansion used preserves gauge and parity symmetries and the correct multivaluation under large gauge transformations as well as the correct parity...

Source: http://arxiv.org/abs/hep-th/9802071v3

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Sep 22, 2013
09/13

by
L. L. Salcedo

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It is argued that the derivative expansion is a suitable method to deal with finite temperature field theory, if it is restricted to spatial derivatives only. Using this method, a simple and direct calculation is presented for the radiatively induced Chern-Simons--like piece of the effective action of (2+1)-dimensional fermions at finite temperature coupled to external gauge fields. The gauge fields are not assumed to be subjected to special constraints, and in particular, they are not required...

Source: http://arxiv.org/abs/hep-th/0201057v1

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Sep 21, 2013
09/13

by
L. L. Salcedo

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The necessity of computing integrals with complex weights over manifolds with a large number of dimensions, e.g., in some field theoretical settings, poses a problem for the use of Monte Carlo techniques. Here it is shown that very general complex weight functions P(x) on R^d can be represented by real and positive weights p(z) on C^d, in the sense that for any observable f, _P = _p, f(z) being the analytical extension of f(x). The construction is extended to arbitrary compact Lie groups.

Source: http://arxiv.org/abs/0706.4359v1

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Sep 18, 2013
09/13

by
L. L. Salcedo

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Explicit exact formulas are presented, for the leading order term in a strict chiral covariant derivative expansion, for the abnormal parity component of the effective action of two- and four-dimensional Dirac fermions in presence of scalar, pseudo-scalar, vector and axial vector background fields. The formulas hold for completely general internal symmetry groups and general configurations. In particular the scalar and pseudo-scalar fields need not be on the chiral circle.

Source: http://arxiv.org/abs/hep-th/0012174v2

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Jul 20, 2013
07/13

by
L. L. Salcedo

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Following Osipov and Hiller, a generalized heat kernel expansion is considered for the effective action of bosonic operators. In this generalization, the standard heat kernel expansion, which counts inverse powers of a c-number mass parameter, is extended by allowing the mass to be a matrix in flavor space. We show that the generalized heat kernel coefficients can be related to the standard ones in a simple way. This holds with or without trace and integration over spacetime, to all orders and...

Source: http://arxiv.org/abs/hep-th/0107133v2

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Sep 18, 2013
09/13

by
L. L. Salcedo

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Diagonal matrix elements of pseudodifferential operators are needed in order to compute effective Lagrangians and currents. For this purpose the method of symbols is often used, which however lacks manifest covariance. In this work the method of covariant symbols, introduced by Pletnev and Banin, is extended to curved space-time with arbitrary gauge and coordinate connections. For the Riemannian connection we compute the covariant symbols corresponding to external fields, the covariant...

Source: http://arxiv.org/abs/hep-th/0606071v2

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Sep 18, 2013
09/13

by
L. L. Salcedo

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It is shown, under mild assumptions, that classical degrees of freedom dynamically coupled to quantum ones do not inherit their quantum fluctuations. It is further shown that, if the assumptions are strengthen by imposing the existence of a canonical structure, only purely classical or purely quantum dynamics are allowed.

Source: http://arxiv.org/abs/hep-th/9509089v1

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Sep 21, 2013
09/13

by
L. L. Salcedo

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The heat kernel in curved space-time is computed to fourth order in a strict expansion in the number of covariant derivatives. The computation is made for arbitrary non abelian gauge and scalar fields and for the Riemann connection in the coordinate sector. The expressions obtained hold for arbitrary tensor representations of the matter field. Complete results are presented for the diagonal matrix elements and for the trace of the heat kernel operator. In addition, Chan's formula is extended to...

Source: http://arxiv.org/abs/0706.1875v2

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Sep 19, 2013
09/13

by
L. L. Salcedo

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In this Comment I point out some limitations of the proposal of Prezhdo and Brooksby for coupling quantum and classical degrees of freedom (Phys.Rev.Lett.86(2001)3215) if it is pushed too far.

Source: http://arxiv.org/abs/quant-ph/0302127v1

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Sep 18, 2013
09/13

by
L. L. Salcedo

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It is argued that the ambiguity introduced by the renormalization in the effective action of a four-dimensional renormalizable quantum field theory is at most a local polynomial action of canonical dimension four. The allowed ambiguity in the expected stress-energy tensor of a massive scalar field is severely restricted by this fact.

Source: http://arxiv.org/abs/gr-qc/9903057v2

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Sep 23, 2013
09/13

by
L. L. Salcedo

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Let a ``complex probability'' be a normalizable complex distribution $P(x)$ defined on $\R^D$. A real and positive probability distribution $p(z)$, defined on the complex plane $\C^D$, is said to be a positive representation of $P(x)$ if $\langle Q(x)\rangle_P = \langle Q(z)\rangle_p$, where $Q(x)$ is any polynomial in $\R^D$ and $Q(z)$ its analytical extension on $\C^D$. In this paper it is shown that every complex probability admits a real representation and a constructive method is given....

Source: http://arxiv.org/abs/hep-lat/9607044v1

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7.0

Sep 22, 2013
09/13

by
L. L. Salcedo

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The multiscattering problem is studied in the matrix density formalism. We study how to isolate the quasi-classical degrees of freedom in order to connect with a cascade approach. The different problems that arise, as well as their possible solutions, are discussed and exemplified with a pion-nucleus model.

Source: http://arxiv.org/abs/nucl-th/0205047v2

7
7.0

Sep 19, 2013
09/13

by
J. Caro; L. L. Salcedo

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The dynamics of systems composed of a classical sector plus a quantum sector is studied. We show that, even in the simplest cases, (i) the existence of a consistent canonical description for such mixed systems is incompatible with very basic requirements related to the time evolution of the two sectors when they are decoupled. (ii) The classical sector cannot inherit quantum fluctuations from the quantum sector. And, (iii) a coupling among the two sectors is incompatible with the requirement of...

Source: http://arxiv.org/abs/quant-ph/9812046v2

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Sep 23, 2013
09/13

by
F. J. Moral-Gamez; L. L. Salcedo

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The method of covariant symbols of Pletnev and Banin is extended to space-times with topology $\R^n\times S^1\times ... \times S^1$. By means of this tool, we obtain explicit formulas for the diagonal matrix elements and the trace of the heat kernel at finite temperature to fourth order in a strict covariant derivative expansion. The role of the Polyakov loop is emphasized. Chan's formula for the effective action to one loop is similarly extended. The expressions obtained formally apply to a...

Source: http://arxiv.org/abs/1110.6300v2

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Sep 18, 2013
09/13

by
L. L. Salcedo; E. Ruiz Arriola

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We use the $\zeta$-function regularization and an integral representation of the complex power of a pseudo differential operator, to give an unambiguous definition of the determinant of the Dirac operator. We bring this definition to a workable form by making use of an asymmetric Wigner representation. The expression so obtained is amenable to several treatments of which we consider in detail two, the inverse mass expansion and the gradient expansion, with concrete examples. We obtain explicit...

Source: http://arxiv.org/abs/hep-th/9412140v1

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5.0

Sep 18, 2013
09/13

by
E. Ruiz Arriola; L. L. Salcedo

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The chiral and scale anomalies of a very general class of non local Dirac operators are computed using the $\zeta$-function definition of the fermionic determinant. For the axial anomaly all new terms introduced by the non locality are shown to be removable by counterterms and such counterterms are also explicitly computed. It is verified that the non local Dirac operators have the standard minimal anomaly in Bardeen's form.

Source: http://arxiv.org/abs/hep-th/9811073v1

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Sep 23, 2013
09/13

by
C. Garcia-Recio; L. L. Salcedo

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Following a suggestion by Smit, the CP odd terms of the effective action of the Standard Model, obtained by integration of quarks and leptons, are computed to sixth order within a strict covariant derivative expansion approach. No other approximations are made. The final result so derived includes all Standard Model gauge fields and Higgs. Remarkably, at the order considered in this work, all parity violating contributions turn out to be zero. Non vanishing CP violating terms are obtained in...

Source: http://arxiv.org/abs/0903.5494v2

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Sep 17, 2013
09/13

by
C. García-Recio; L. L. Salcedo

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A method is presented for the computation of the one-loop effective action at finite temperature and density. The method is based on an expansion in the number of spatial covariant derivatives. It applies to general background field configurations with arbitrary internal symmetry group and space-time dependence. Full invariance under small and large gauge transformations is preserved without assuming stationary or Abelian fields nor fixing the gauge. The method is applied to the computation of...

Source: http://arxiv.org/abs/hep-th/0007183v2

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Sep 19, 2013
09/13

by
E. Ruiz Arriola; L. L. Salcedo

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We consider the extended SU(3) Nambu and Jona-Lasinio model with explicit vector couplings in the presence of external fields. We study the chiral anomaly in this model and its implications on the properties of the nucleon described as a chiral soliton of three valence quarks bounded in mesonic background fields. For the model to reproduce the QCD anomaly it is necessary to subtract suitable local and polynomial counterterms in the external and dynamical vector and axial-vector fields. We...

Source: http://arxiv.org/abs/nucl-th/9501026v2

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14

Sep 24, 2013
09/13

by
V. E. Cachorro; L. L. Salcedo

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New improvements to compute Mie scattering quantities are presented. They are based on a detailed analysis of the various sources of error in Mie computations and on mathematical justifications. The algorithm developed on these improvements proves to be reliable and efficient, without size ($x=2\pi R/\lambda$) nor refractive index ($m=m_R-{\rm i}m_I$) limitations, and the user has a choice to fix in advance the desired precision in the results. It also includes a new and efficient method to...

Source: http://arxiv.org/abs/physics/0103052v1

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Jul 20, 2013
07/13

by
E. Ruiz Arriola; L. L. Salcedo

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The anomalies of a very general class of non local Dirac operators are computed using the $\zeta$-function definition of the fermionic determinant and an asymmetric version of the Wigner transformation. For the axial anomaly all new terms introduced by the non locality can be brought to the standard minimal Bardeen's form. Some extensions of the present techniques are also commented.

Source: http://arxiv.org/abs/hep-th/9910230v1

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Sep 19, 2013
09/13

by
C. Garcia-Recio; L. L. Salcedo

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Tables of scalar factors are presented for 63x63 and 120x63 in SU(8)$\supset$SU(4)xSU(2), and for 35x35 and 56x35 in SU(6)$\supset$SU(3)xSU(2). Related tables for SU(4)$\supset$SU(3)xU(1) and SU(3)$\supset$SU(2)xU(1) are also provided so that the Clebsch-Gordan coefficients can be completely reconstructed. These are suitable to study meson-meson and baryon-meson within a spin-flavor symmetric scheme.

Source: http://arxiv.org/abs/1010.5667v1

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Sep 23, 2013
09/13

by
C. Garcia-Recio; L. L. Salcedo

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A short derivation is given of the weak gravitational field approximation to the scalar massless propagator in Schwarzschild spacetime obtained by Paszko using the path-integral approach. The contribution from the direct coupling of the quantum field to the scalar curvature is explictly included. The propagator complies with Hadamard's pattern, and the vacuum state is consistent with the perturbative version of the Boulware vacuum. The momentum space propagator is computed for massless or...

Source: http://arxiv.org/abs/1303.6620v1

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Sep 22, 2013
09/13

by
E. Megias; E. Ruiz Arriola; L. L. Salcedo

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A recently proposed phenomenological model, which includes non perturbative effects from dimension two gluon condensates, is applied to analyze the available lattice data for the heavy quark free energy in the deconfined phase of quenched QCD. For large $q\bar{q}$ separations we recover previous results for the Polyakov loop, exhibiting unequivocal condensate contributions. For the $q\bar{q}$ potential at finite temperature and finite separation we find that a good overall description of the...

Source: http://arxiv.org/abs/hep-ph/0702055v1

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Sep 24, 2013
09/13

by
E. Megias; E. Ruiz Arriola; L. L. Salcedo

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We describe how the inclusion of the gluonic Polyakov loop incorporates large gauge invariance and drastically modifies finite temperature calculations in chiral quark models after color neutral states are singled out. This generates an effective theory of quarks and Polyakov loops as basic degrees of freedom. We find a strong suppression of finite temperature effects in hadronic observables triggered by approximate triality conservation (Polyakov cooling), so that while the center symmetry...

Source: http://arxiv.org/abs/hep-ph/0412308v3

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Sep 21, 2013
09/13

by
E. Megias; E. Ruiz Arriola; L. L. Salcedo

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The Polyakov loop has been used repeatedly as an order parameter in the deconfinement phase transition in QCD. We argue that, in the confined phase, its expectation value can be represented in terms of hadronic states, similarly to the hadron resonance gas model for the pressure. Specifically, L(T) \approx 1/2\sum_\alpha g_\alpha \,e^(-\Delta_\alpha/T), where g_\alpha are the degeneracies and \Delta_\alpha are the masses of hadrons with exactly one heavy quark (the mass of the heavy quark...

Source: http://arxiv.org/abs/1204.2424v2

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Sep 19, 2013
09/13

by
C. Garcia-Recio; J. Nieves; L. L. Salcedo

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The construction of an extended version of the Weinberg-Tomozawa Lagrangian, in which baryons and mesons form spin-flavor multiplets, is reviewed and some of its properties discussed, for an arbitrary number of colors and flavors. The coefficient tables of spin-flavor irreducible representations related by crossing between the $s$-, $t$- and $u$-channels are explicitly constructed.

Source: http://arxiv.org/abs/hep-ph/0610204v1

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Sep 18, 2013
09/13

by
C. Garcia-Recio; J. Nieves; L. L. Salcedo

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A consistent SU(6) extension of the Weinberg-Tomozawa meson-baryon chiral Lagrangian is constructed which incorporates vector meson and baryon decuplet degrees of freedom. The corresponding Bethe-Salpeter approximation predicts the existence of an isoscalar spin-parity ${3/2}^-$ $K^*N$ bound state (strangeness +1) with a mass around 1.7--1.8$ $GeV. It is the highest hypercharge state of an antidecuplet SU(3) representation and it is unstable through $K^*$ decay. The estimated width of this...

Source: http://arxiv.org/abs/hep-ph/0505233v2

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Sep 22, 2013
09/13

by
E. Megias; E. Ruiz Arriola; L. L. Salcedo

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The dimension two gluon condensate has been used previously within a simple phenomenological model to describe power corrections from available lattice data for the renormalized Polyakov loop and the heavy quark-antiquark free energy in the deconfined phase of QCD (hep-ph/0505215,hep-ph/0702055). The QCD trace anomaly of gluodynamics also shows unequivocal inverse temperature power corrections which may be encoded as dimension two gluon condensate. We analyze lattice data of the trace anomaly...

Source: http://arxiv.org/abs/0805.4579v1

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Sep 23, 2013
09/13

by
E. Megias; E. Ruiz Arriola; L. L. Salcedo

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The heat kernel expansion for field theory at finite temperature is constructed. It is based on the imaginary time formalism and applies to generic Klein-Gordon operators in flat space-time. Full gauge invariance is manifest at each order of the expansion and the Polyakov loop plays an important role at any temperature. The expansion is explicitly worked out up to operators of dimension six included. The method is then applied to compute the one loop effective action of QCD at finite...

Source: http://arxiv.org/abs/hep-ph/0312133v1

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Sep 18, 2013
09/13

by
E. Megias; E. Ruiz Arriola; L. L. Salcedo

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We show that recent available lattice data for the renormalized Polyakov loop above the deconfinement phase transition exhibit unequivocal inverse power temperature corrections driven by a dimension 2 gluon condensate. This simple ansatz provides a good overall description of the data throughout the deconfinement phase until near the critical temperature with just two parameters. One of the parameters is consistent with perturbation theory while a second, non perturbative, parameter provides a...

Source: http://arxiv.org/abs/hep-ph/0505215v3

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Sep 23, 2013
09/13

by
E. Megias; E. Ruiz Arriola; L. L. Salcedo

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The Polyakov loop is an order parameter to the confinement-deconfinement phase transition in pure gluodynamics. Recently a simple phenomenological model has been proposed to describe the available lattice data for the renormalized Polyakov loop in the deconfinement phase (hep-ph/0505215). These data exhibit unequivocal inverse power temperature corrections driven by a dimension two gluon condensate. The heavy quark free energy is also studied and compared to lattice data.

Source: http://arxiv.org/abs/hep-ph/0510114v1

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Sep 18, 2013
09/13

by
E. Megias; E. Ruiz Arriola; L. L. Salcedo

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The lower order terms of the heat kernel expansion at coincident points are computed in the context of finite temperature quantum field theory for flat space-time and in the presence of general gauge and scalar fields which may be non Abelian and non stationary. The computation is carried out in the imaginary time formalism and the result is fully consistent with invariance under topologically large and small gauge transformations. The Polyakov loop is shown to play a fundamental role.

Source: http://arxiv.org/abs/hep-th/0212237v1

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Sep 21, 2013
09/13

by
J. Caro; E. Ruiz Arriola; L. L. Salcedo

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The $\sigma$-$\omega$ model of nuclei is studied at leading order in the $1/N$ expansion thereby introducing the self consistent Hartree approximation, the Dirac sea corrections and the one fermion loop meson self energies in a unified way. For simplicity, the Dirac sea is further treated within a semiclassical expansion to all orders. The well-known Landau pole vacuum instability appearing in this kind of theories is removed by means of a scheme recently proposed in this context. The effect of...

Source: http://arxiv.org/abs/nucl-th/9609031v1

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Sep 19, 2013
09/13

by
E. Megias; E. Ruiz Arriola; L. L. Salcedo

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We describe results for the confinement-deconfinement phase transition as predicted by the Nambu--Jona-Lasinio model where the local and quantum Polyakov loop is coupled to the constituent quarks in a minimal way (PNJL). We observe that the leading correlation of two Polyakov loops describes the chiral transition accurately. The effects of the current quark mass on the transition are also analysed.

Source: http://arxiv.org/abs/hep-ph/0610095v1

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Jul 20, 2013
07/13

by
E. Ruiz Arriola; L. L. Salcedo; E. Megias

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We show how excited states in QCD can be profitably used to build up the Polyakov loop in the fundamental representation at temperatures below the hadron-quark-gluon crossover. The conditions under which a Hagedorn temperature for the Polyakov loop can be defined are analysed.

Source: http://arxiv.org/abs/1304.2245v2

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Sep 18, 2013
09/13

by
J. Caro; E. Ruiz Arriola; L. L. Salcedo

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Dirac sea corrections for bulk properties of finite nuclei are computed within a self-consistent scheme in the $\sigma$-$\omega$ model. The valence part is treated in the Hartree approximation whereas the sea contribution is evaluated semiclassically up to fourth order in $\hbar$. Numerically, we find a quick convergence of the semiclassical expansion; the fourth order contributing much less than one percent to the binding energy per nucleon.

Source: http://arxiv.org/abs/nucl-th/9601033v1

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Sep 23, 2013
09/13

by
E. Megias; E. Ruiz Arriola; L. L. Salcedo

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The trace anomaly of gluodynamics on the lattice shows clear fingerprints of a dimension two condensate above the phase transition. The condensate manifests itself through even powers of the inverse temperature while the total perturbative contribution corresponds to a mild temperature dependence and turns out to be compatible with zero within errors. We try several resummation methods based on a renormalization group improvement. The trace anomaly data are analyzed and compared with other...

Source: http://arxiv.org/abs/0903.1060v2

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Sep 19, 2013
09/13

by
C. Garcia-Recio; J. Nieves; L. L. Salcedo

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Starting from a consistent SU(6) extension of the Weinberg-Tomozawa (WT) meson-baryon chiral Lagrangian (Phys. Rev. D74 (2006) 034025), we study the s-wave meson-baryon resonances in the strangeness S=-3 and negative parity sector. Those resonances are generated by solving the Bethe-Salpeter equation with the WT interaction used as kernel. The considered mesons are those of the 35-SU(6)-plet, which includes the pseudoscalar (PS) octet of pions and the vector (V) nonet of the rho meson. For...

Source: http://arxiv.org/abs/hep-ph/0610353v1

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5.0

Sep 19, 2013
09/13

by
C. Garcia-Recio; J. Nieves; L. L. Salcedo

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Vector meson degrees of freedom are incorporated into the Weinberg-Tomozawa (WT) meson-baryon chiral Lagrangian by using a scheme which relies on spin--flavor SU(6) symmetry. The corresponding Bethe-Salpeter approximation successfully reproduces previous SU(3)--flavor WT results for the lowest-lying s--wave negative parity baryon resonances, and it also provides some information on the dynamics of the heavier ones. Moreover, it also predicts the existence of an isoscalar spin-parity $\frac32^-$...

Source: http://arxiv.org/abs/hep-ph/0610127v2

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10.0

Sep 22, 2013
09/13

by
E. Megias; E. Ruiz Arriola; L. L. Salcedo; W. Broniowski

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We analyze the recently proposed Spectral Quark Model in the light of Chiral Perturbation Theory in curved space-time. In particular, we calculate the chiral coefficients $L_1, ..., L_{10}$, as well as the coefficients $L_{11}$, $L_{12}$, and $L_{13}$, appearing when the model is coupled to gravity. The analysis is carried for the SU(3) case. We analyze the pattern of chiral symmetry breaking as well as elaborate on the fulfillment of anomalies. Matching the model results to resonance meson...

Source: http://arxiv.org/abs/hep-ph/0403139v2